1 files changed, 202 insertions, 0 deletions

diff --git a/src/examples/suspend_resume_epoll.c b/src/examples/suspend_resume_epoll.c
new file mode 100644
index 00000000..adff673c
--- /dev/null
+++ b/src/examples/suspend_resume_epoll.c
@@ -0,0 +1,202 @@
+/*
+     This file is part of libmicrohttpd
+     Copyright (C) 2018 Christian Grothoff (and other contributing authors)
+
+     This library is free software; you can redistribute it and/or
+     modify it under the terms of the GNU Lesser General Public
+     License as published by the Free Software Foundation; either
+     version 2.1 of the License, or (at your option) any later version.
+
+     This library is distributed in the hope that it will be useful,
+     but WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     Lesser General Public License for more details.
+
+     You should have received a copy of the GNU Lesser General Public
+     License along with this library; if not, write to the Free Software
+     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+/**
+ * @file suspend_resume_epoll.c
+ * @brief example for how to use libmicrohttpd with epoll() and
+ *        resume a suspended connection
+ * @author Robert D Kocisko
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <microhttpd.h>
+#include <sys/epoll.h>
+#include <sys/timerfd.h>
+#include <limits.h>
+
+#define TIMEOUT_INFINITE -1
+
+struct Request {
+  struct MHD_Connection *connection;
+  int timerfd;
+};
+
+
+static int epfd;
+
+static struct epoll_event evt;
+
+
+static int
+ahc_echo (void *cls,
+          struct MHD_Connection *connection,
+          const char *url,
+          const char *method,
+          const char *version,
+          const char *upload_data, size_t *upload_data_size, void **ptr)
+{
+  struct MHD_Response *response;
+  int ret;
+  struct Request* req;
+  struct itimerspec ts;
+  (void)url;               /* Unused. Silence compiler warning. */
+  (void)version;           /* Unused. Silence compiler warning. */
+  (void)upload_data;       /* Unused. Silence compiler warning. */
+  (void)upload_data_size;  /* Unused. Silence compiler warning. */
+
+  req = *ptr;
+  if (!req)
+  {
+
+    req = malloc(sizeof(struct Request));
+    req->connection = connection;
+    req->timerfd = 0;
+    *ptr = req;
+    return MHD_YES;
+  }
+
+  if (req->timerfd)
+  {
+    // send response (echo request url)
+    response = MHD_create_response_from_buffer (strlen (url),
+                                                (void *) url,
+                                                MHD_RESPMEM_MUST_COPY);
+    ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
+    MHD_destroy_response (response);
+    return ret;
+  }
+  else
+  {
+    // create timer and suspend connection
+    req->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK);
+    if (-1 == req->timerfd)
+    {
+      printf("timerfd_create: %s", strerror(errno));
+      return MHD_NO;
+    }
+    evt.events = EPOLLIN;
+    evt.data.ptr = req;
+    if (-1 == epoll_ctl(epfd, EPOLL_CTL_ADD, req->timerfd, &evt))
+    {
+      printf("epoll_ctl: %s", strerror(errno));
+      return MHD_NO;
+    }
+    ts.it_value.tv_sec = 1;
+    ts.it_value.tv_nsec = 0;
+    ts.it_interval.tv_sec = 0;
+    ts.it_interval.tv_nsec = 0;
+    if (-1 == timerfd_settime(req->timerfd, 0, &ts, NULL))
+    {
+      printf("timerfd_settime: %s", strerror(errno));
+      return MHD_NO;
+    }
+    MHD_suspend_connection(connection);
+    return MHD_YES;
+  }
+}
+
+
+static int
+connection_done(struct MHD_Connection *connection,
+                void **con_cls,
+                enum MHD_RequestTerminationCode toe)
+{
+  free(*con_cls);
+}
+
+
+int
+main (int argc,
+      char *const *argv)
+{
+  struct MHD_Daemon *d;
+  const union MHD_DaemonInfo * info;
+  int current_event_count;
+  struct epoll_event events_list[1];
+  struct Request *req;
+  uint64_t timer_expirations;
+
+  if (argc != 2)
+    {
+      printf ("%s PORT\n", argv[0]);
+      return 1;
+    }
+  d = MHD_start_daemon (MHD_USE_EPOLL | MHD_ALLOW_SUSPEND_RESUME,
+                        atoi (argv[1]),
+                        NULL, NULL, &ahc_echo, NULL,
+                        MHD_OPTION_NOTIFY_COMPLETED, &connection_done, NULL,
+                        MHD_OPTION_END);
+  if (d == NULL)
+    return 1;
+
+  info = MHD_get_daemon_info(d, MHD_DAEMON_INFO_EPOLL_FD);
+  if (info == NULL)
+    return 1;
+
+  epfd = epoll_create1(EPOLL_CLOEXEC);
+  if (-1 == epfd)
+    return 1;
+
+  evt.events = EPOLLIN;
+  evt.data.ptr = NULL;
+  if (-1 == epoll_ctl(epfd, EPOLL_CTL_ADD, info->epoll_fd, &evt))
+    return 1;
+
+  while (1)
+  {
+    int timeout;
+    MHD_UNSIGNED_LONG_LONG to;
+
+    if (MHD_YES !=
+        MHD_get_timeout (d,
+                         &to))
+      timeout = TIMEOUT_INFINITE;
+    else
+      timeout = (to < INT_MAX - 1) ? (int) to : (INT_MAX - 1);
+    current_event_count = epoll_wait(epfd, events_list, 1, timeout);
+
+    if (1 == current_event_count)
+    {
+      if (events_list[0].data.ptr)
+      {
+        // A timer has timed out
+        req = events_list[0].data.ptr;
+        // read from the fd so the system knows we heard the notice
+        if (-1 == read(req->timerfd, &timer_expirations, sizeof(timer_expirations)))
+        {
+          return 1;
+        }
+        // Now resume the connection
+        MHD_resume_connection(req->connection);
+      }
+    }
+    else if (0 == current_event_count)
+    {
+      // no events: continue
+    }
+    else
+    {
+      // error
+      return 1;
+    }
+    if (! MHD_run(d))
+      return 1;
+  }
+
+  return 0;
+}